RESUMO
Objective To explore the effects of deoxynivalenol (DON) on apoptosis of human gastric carcinoma cell line SNU in vitro. Methods SNU cells were treated with DON at different concentrations (50, 100, 1000, 2000 μg/L) for 12 hours, and then cells were harvested for cell apoptosis by flow cytometric (FCM) DNA analysis and the expression of Bax, Bcl-2 and Caspase-3 at protein level with FCM and Western blotting. Results FCM results showed that the apoptosis rates of SNU cells in DON treatment groups were all higher than that in control, especially in DON 1000 μg/L and 2000 μg/L groups (P<0.05). In the concentration range from 50 to 2000 μg/L, a significant concentration-depended response correlation could be found between apoptosis rate and DON concentration (r =0.940, P <0.01). FCM and Western blotting showed Bax and Caspase-3 expression in often SNU cells DON treatment for 12 hours were up-regulated while that of Bcl-2 was down-regulated. Conclusion DON can induce apoptosis of SNU cells in vitro in dose-dependent manner, and possible mechanisms of apoptosis induction effects may be up-regulation of the expression of Bax and down-regulation of that of Bcl-2 and activation of the key enzyme of apoptosis Caspase-3.
RESUMO
Objective: To investigate the optimal gene transfer protocols of hematopoietic cells mediated by retrovirus. Methods: Murine bone marrow cells were infected by co-culture with murine bone marrow stromal cell line TC-1 or retro-virus packaging cells or retrovirus supernatant. Human mdr-1 and enhanced green fluorescent protein (EGFP) were used as report genes. Results: Stromal cells could greatly increase the gene transfer efficiency when compared with that of supernatant transfection. Transduction efficiency was highest when infected BM cells were co-cultured with virus producer cells. Conculsion: It may be clinically feasible in gene therapy to perform retroviral transduction by co-culture of target cells with stromal cells or cell lines.